Wednesday, December 28, 2011

No time left to adapt to Peru's melting glaciers

Stephen Leahy in IPS via Tierramérica: The water supplied by the glaciers of the Cordillera Blanca, vital to a huge region of northwest Peru, is decreasing 20 years sooner than expected, according to a new study. Water flows from the region's melting glaciers have already peaked and are in decline, Michel Baraer, a glaciologist at Canada's McGill University, told Tierramérica. This is happening 20 to 30 years earlier than forecasted.

"Our study reveals that the glaciers feeding the Río Santa watershed are now too small to maintain past water flows. There will be less water, as much as 30 percent less during the dry season," said Baraer, lead author of the study "Glacier Recession and Water Resources in Peru’s Cordillera Blanca", published Dec. 22 in the Journal of Glaciology.

When glaciers begin to shrink in size, they generate "a transitory increase in runoff as they lose mass," the study notes. However, Baraer explained, the water flowing from a glacier eventually hits a plateau and from this point onwards there is a decrease in the discharge of melt water. "The decline is permanent. There is no going back."

Part of the South American Andes Mountain chain, the Cordillera Blanca is a series of snow-covered peaks running north to south, parallel to the Cordillera Negra, located further west. Between the two ranges lies the Callejón de Huaylas, through which the Río Santa runs, eventually emptying into the Pacific Ocean.

The tropical glaciers of the Andes Mountains are in rapid decline, losing 30 to 50 percent of their ice in the last 30 years, according to the French Institute for Research and Development (IRD). Most of the decline has been since 1976, IRD reported, due to rising temperatures in the region as a result of climate change. In Bolivia, the Chacaltaya glacier disappeared in 2009....
Stephen Leahy in IPS via Tierramérica: The water supplied by the glaciers of the Cordillera Blanca, vital to a huge region of northwest Peru, is decreasing 20 years sooner than expected, according to a new study. Water flows from the region's melting glaciers have already peaked and are in decline, Michel Baraer, a glaciologist at Canada's McGill University, told Tierramérica. This is happening 20 to 30 years earlier than forecasted.

"Our study reveals that the glaciers feeding the Río Santa watershed are now too small to maintain past water flows. There will be less water, as much as 30 percent less during the dry season," said Baraer, lead author of the study "Glacier Recession and Water Resources in Peru’s Cordillera Blanca", published Dec. 22 in the Journal of Glaciology.

When glaciers begin to shrink in size, they generate "a transitory increase in runoff as they lose mass," the study notes. However, Baraer explained, the water flowing from a glacier eventually hits a plateau and from this point onwards there is a decrease in the discharge of melt water. "The decline is permanent. There is no going back."

Part of the South American Andes Mountain chain, the Cordillera Blanca is a series of snow-covered peaks running north to south, parallel to the Cordillera Negra, located further west. Between the two ranges lies the Callejón de Huaylas, through which the Río Santa runs, eventually emptying into the Pacific Ocean.

The tropical glaciers of the Andes Mountains are in rapid decline, losing 30 to 50 percent of their ice in the last 30 years, according to the French Institute for Research and Development (IRD). Most of the decline has been since 1976, IRD reported, due to rising temperatures in the region as a result of climate change. In Bolivia, the Chacaltaya glacier disappeared in 2009....

Llaca glacier located in central Peru in the Cordillera Blanca (White Range). Shot by Edubucher, Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license

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